DHC8FO

I'm tearing into the top end to take off the head and figured I could just slide out the head to the top as the timing belt had snapped. But no, it didn't snap. Everything was intact. Even more puzzling was the #1 intake valve had actually hit the head. WTF? I'm wondering if the head had been assembled incorrectly (timing) or the head was machined below tolerences and installed. But it had been running (so I was told).

I plan to check the deck height, what do you think happened? Frankly I'm at a loss.

There was alot of loose carbon build up, and the head was cleaner than the rest of the engine. I'm thinking poor job of assembly, but it must have run for some time to have this much carbon.

tod84944

Missed gear with a serious over-rev

DHC8FO

Belt seemed to have some tension on it but was older. The guy was older and didn't seem to be the street racer type, but who knows. Maybe the belt was just loose enough to jump a few teeth.

tod84944

This is true, 2 teeth could bend just one valve. But....... most of the time when it is timing belt related, it is the exhuaust valves.

DHC8FO

Sorry, it actually was an exhaust valve, now that I look at it.